Which Unleashed AP for wireless video production monitoring?

I build apps for, and support, wireless video monitoring for film/video production. Typically there will be one or two Wi-Fi-capable cameras (or camera-attached Wi-Fi encoders) that send video to iPhones / iPads. Each camera sends data streams at .8 Mbps to 2.5 Mbps; some send streams of JPEGs over UDP (unicast), while others send H.264 video over RTSP or HTTP Live Streaming (with up to 4 receiving clients).

This all works great... until we arrive at a location already crowded with Wi-Fi traffic, at which point things can fall apart in a hurry. Every location is different, and there's no time for an advance site survey. Cameras are typically within 50 feet of the receiving devices... but not always. Their position and orientation--and thus the position and orientation of their built-in radios--are determined by production requirements, not radio optimization, and often the darned things move around during a shot. And if the location is, say, a tech startup in a downtown San Francisco open-plan office, there can be dozens of competing Wi-Fi networks (and microwave ovens) all fighting for the same bandwidth.

Scuttlebutt has it that a Ruckus AP will help us cut through the clutter and deliver a stable signal, and I've seen this in action: a Wi-Fi-heavy trade show where Ruckus-connected transmitters sent flawless video while my own, identical transmitter, using only its built-in AP or a cheap consumer Wi-Fi router, couldn't even connect to a receiving client half the time, never mind send clean video.

So how do I decide which Ruckus Unleashed AP to select, and how do I advise clients which one they should pick? Which technical parameters are the most significant for our application: radio chains & streams? Antenna patterns per band? Gains? Interference mitigation?

Obviously, if cost were no object, an R710 / T710 would be the go-to choice. But will it perform substantially better than an R310 for this rather odd use case? And if so, *why*? Many of my clients are very cheap--erm, highly cost-conscious--so having some idea of what parameters are most important would help me make sense of the various spec sheets, and steer us towards an optimal price/performance tradeoff. Thanks!